Effect of social feeding environment on the feeding behaviour of dairy cows and their willingness to consume a novel feed

Dairy cows are often exposed to novel situations and may show a strong behavioural response to novel feeds. To test the impact of social contact while feeding and the reaction of mature cows towards a novel feed we compared: 1) animals fed individually and 2) cows fed socially (in pairs). It was hypothesized that animals feeding together would show similar behavioural patterns and a greater willingness to consume a novel feed product. Twelve Holstein cows (parity = 3.3 ± 1.3; mean ± SD) were assigned to 4 groups of 3 animals (each with 1 fed alone: Single cow and 2 fed socially: Pair 1 and Pair 2 cows). Two feed types were offered separately: a familiar food: total mixed ration (TMR) and, 5 kg of carrots topped with 6 kg of TMR (as-fed). Each group was observed for 10 d, each consisting of 3 periods: 1) 4 d of adaptation (only TMR); 2) d 5-7 the carrots were introduced to the Single cow and to 1 of the 2 cows fed socially (Pair 1 cow); and 3) from d 8-10 all 3 cows were fed carrots and TMR. Dry matter intake (DMI), feeding behaviour, rumination time, and sorting activity were monitored for each animal. Cow behaviour was observed for an hour after each feed delivery. No differences in DMI of TMR (27.1 kg/d) or carrots (0.09 kg/d) and feeding time (193.9 min/d) were found between any animal eating as a Single or in Pairs. However, the DMI of carrots increased from period 2 to period 3 (0.04-0.12 kg/d; P = 0.03). In period 2, Pair 2 (subordinate) animals ate faster than the other cows (0.19 vs 0.13 and 0.12 kg/min; P = 0.05). In period 2, Pair 2 cows tended to select more for medium particles (106 vs 102%; P = 0.08) and sorted to a greater extent against short (97 vs 99%; P = 0.02) and fine fractions (89 vs 97 and 96%; P = 0.05). Overall, the intake of carrots was very low in all treatments, however, animals consumed more carrots in the third period. These results suggest that the acceptance of novel food might increase with the length of exposure. It is also concluded that animals showed similar feeding behavioural patterns regardless of feeding situation.